Can't categorize exercise

[Gnomesy]

This is my understanding how my charge 4 works, I can only store 6 activities on my watch and there's only certain ones that can go on there. If I'm doing another activity I choose "outdoor activity" and then go on my app and change it through "categorize exercise"?

If that's the correct way to do it, when I do that the only options I get are the ones that are already on my watch, so I go for a surf or kayak I can't change it to reflect that.

It only seems to happen if I turn my watch on to track my activity and the GPS is running so the app shows an image of where I've been. When my watch automatically picks up that I'm doing something, like the other day I did some gardening and it came up with an activity but no GPS image, I was able to change it to gardening. 

What am I doing wrong? I have paid for a Fitbit subscription, I've logged out, removed app and restarted my iphone. I don't want to let it automatically pick up I'm doing something so I can change activity because I'd like to track where I am.

Thanks

[JohnnyRow]

See How do I track my workouts with my Fitbit device? 

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